Next Generation Sequencing
Oncogenic mutations within the KIT gene occur in a subset of melanomas, most frequently in those of mucosal (~20%) and acral (~15%) types, and less commonly in those from cutaneous and conjunctival sites. These KIT mutations are predicted to be activating, and are similar to those found in imatinib-responsive cancers of other types. Testing for KIT mutation in melanoma may aid in identifying patients who might benefit from therapies such as imatinib that target activated KIT. This DNA test is performed by targeted next-generation sequencing (NGS) and will detect KIT mutations within the sequenced regions of exons 8, 9, 11, 13 and 17 (see Additional Information below for specific regions sequenced). Specimens should contain an adequate proportion of neoplastic nuclei (>10%) in the areas to be extracted to ensure mutation detection.
Interpretive report provided.
This test will only detect the mutations within specific gene regions (See Additional Information below for specific information). This test may fail to detect mutations below the limit of detection of this assay (approximately 5%). Discordant results are rarely observed between metastatic and primary tumors. This test cannot distinguish between somatic and germline alterations. Additional testing may be required if there is concern for a clinically relevant germline alteration. The clinical implications of the findings as indicated in the test report may change based on evolution of the scientific literature.
- KIT Mutation Detection - Melanoma
- KIT Mutation Detection for Imatinib Therapy
- c-KIT Mutation
- KIT Exon 11, 13, 17 Mutations
For formalin-fixed, paraffin-embedded tissue, a block containing an area with a high percentage of neoplastic cells (for micro-/macro-dissection) is preferred. Unstained, UNBAKED slides (5-8, 10-micron slides; 10-15 if few neoplastic cells are present) with associated H&E stained slide are also acceptable. Decalcified tissue or other fixatives will be accepted and the assay attempted, however these may result in failed testing due to degraded nucleic acid. Both blocks and slides should be stored at room temperature. A Diff-Quik or Papanicolaou stained aspirate smear (preferable containing a high percentage and overall amount of neoplastic cells) is also acceptable. Store at room temperature.
Updated on: 12/06/2017
By ordering this test the clinician acknowledges that informed consent has been obtained from the patient as required by applicable state or federal laws and the ordering clinician has authorization from the patient permitting MLabs to report the test results to the ordering clinician. Test includes pathologist interpretation of results billed as a separate additional charge. This test is not available without interpretation.